The present invention relates broadly to the tempering of glass sheets and more particularly to apparatus for tempering glass sheets by the continuous horizontal process.
According to such process, the glass sheets are conveyed horizontally through a furnace in which they are heated to substantially the softening point of the glass and, upon exiting from the furnace, are conveyed upon horizontally spaced conveyor rolls between upper and lower blastheads and rapidly cooled thereby to establish a permanent stress pattern in the sheets.
It has been found that the stress conditions created in the glass sheets during tempering frequently cause the sheets to shatter during such operations. This presents a serious problem in that the broken glass becomes lodged between the conveyor rolls causing a back-up of succeeding sheets resulting in additional breakage as well as damage to the equipment. Close monitoring of the tempering operations must therefore be maintained to see that the broken glass is removed as quickly as possible. With present methods this is a time consuming and laborious procedure.
The primary object of this invention therefore is the provision of new and novel means whereby the removal of glass sheets that are shattered during the tempering operations can be easily and quickly effected in an efficient manner and with the expenditure of a minimum amount of time and labor.
Another object of the invention is to provide tempering apparatus of the above character in which the upper and lower blastheads are mounted in such a way that they can be readily moved from their normal operating positions to positions which create clear, unobstructed passages between the conveyor rolls permitting the broken glass to fall freely between said rolls and away from the apparatus.
A further object of the invention is to provide means for independently mounting the upper and lower blastheads for pivotal movement such that they can be swung upwardly and downwardly respectively relative to the conveyor rolls to cause the broken glass to be discharged from the apparatus between the conveyor rolls.
Other details, objects and advantages of the invention will become apparent during the following description of the preferred embodiment taken in connection with the accompanying drawings.